1. Field of the Invention
The present invention relates to an image processing method and image processor that perform image processing on a synthesized image obtained by synthesizing a natural image acquired by photography and a computer graphic (CG) image such as clip art contained in a template, and to a program for causing a computer to execute the image processing method.
2. Description of the Related Art
In photo studios, there is service for making, for example, New Year's cards illustrated with photographs, by utilizing a template that consists of New Year's characters, illustrations, and a blank region for inserting photographs. Such New Year's cards arc made by, for example, synthesizing image data obtained by reading out an image recorded on a negative film or obtained with a digital camera, and template data representing a template containing clip art or characters produced by computer processing, and then printing a synthesized image on the basis of the synthesized image data.
Besides photo studios, a synthesized image can also be made by synthesizing an image obtained by a user and a template by an application program for synthesizing and editing images installed in personal computers. This enables users to make post cards easily.
To enhance the picture quality of an image reproduced by printing out image data, an image-processing parameter for image processing, such as a density correction process, a color correction process, a gradation correction process, etc., is computed based on image data, and based on the computed image-processing parameter, image processing is performed on the image data. The image processing renders it possible to obtain a reproduced image with a high picture quality.
Also, by performing image processing on an image obtained by synthesizing an image (natural image) obtained by photographing and a template, a synthesized image with a high picture quality can be obtained.
In the case where a synthesized image that a user obtained with an application program is printed in a photo studio at user's request, an image-processing parameter for image processing is computed from the synthesized image, and image processing is performed on the synthesized image. However, since such a synthesized image contains both a natural image and a computer graphic (CG) image such as clip art contained in a template, the original color and brightness of the CG image will vary if image processing is performed on the synthesized image by the computed image-processing parameter. Also, because a CG image frequently contains primary colors compared to a natural image, the picture quality of a natural image will be degraded if image processing is performed by an image-processing parameter computed from a synthesized image containing a CG image.